Polyurethane foams and processes for preparation

ABSTRACT

Polyurethane foams which may be rendered flame resistant by the addition of flame retardants are produced by reaction between a carbohydrate, a polyisocyanate and water in the presence of a suitable surfactant and polyurethane forming catalyst.

RELATED APPLICATION

This is a division, of application Ser. No. 443,878 filed Nov. 23, 1982;which in turn is a continuation-in-part application of my copendingapplication Ser. No. 328,686 filed Dec. 8, 1981.

BACKGROUND OF THE INVENTION

The present invention relates to foam compositions which may be flameretardant and methods for making same wherein reaction pressures can becontrolled during the foaming process. The foam may be produced with avariety of densities, tensile strength, cell structures and otherphysical properties.

Plastic foams have been utilized as thermal insulating materials, lightweight construction materials, and flotation materials and for a widevariety of other uses because of their excellent properties. Heretofore,their use has been limited in environments where there is danger of firebecause of their substantial fuel contribution, their contribution torapid flame spread and the fact that they generate large quantities ofnoxious smoke on thermal decomposition when burned or heated to anelevated temperature. This has limited the commercial development ofplastic foams. Large amounts of money and much research time have beenexpended in attempts to alleviate these problems.

With the present interest in conserving heating fuel, many existingbuildings are installing additional insulation, and newly constructedbuildings are including more insulation than was formerly used.

The most commonly used type of foam insulation for existing structuresare urea formaldehyde foams, which are foamed in place between theoutside wall and the inside wall of the structure. Unfortunately, theurea formaldehyde foam spontaneously decomposes, releasing formaldehydefumes in quantities which may be toxic. The use of urea formaldehydefoams in construction is prohibited in some building codes for thisreason.

Another type of material often used for insulation is polyurethane foam.However, polyurethane foam provides a substantial fuel contribution,spreads flame rapidly, and releases toxic gases including carbondioxide, carbon monoxide and hydrogen cyanide when burned. The use ofpolyurethane foam for retrofit is not completely satisfactory because ofthe high reaction pressures generated during the foaming process, whichcan be sufficient to separate the wallboard from the wall studs.

Rigid polyurethane foams are generally prepared by reacting an organicpolyisocyanate with a polyol. For most commercial purposes, the reactionis conducted in the presence of a foaming agent, surfactant, catalystand possibly other ingredients. In order to reduce the cost of preparingthese foams, efforts have been made to employ polysaccharides such asstarch or cellulose as a polyol reactant in their preparation. The useof such substrates has been unsatisfactory because of the poor physicalproperties of the foams produced unless they have been modified in someway or supplemented with conventional industrial polyols. Oxyalkylatedstarch yields satisfactory foams, but the direct oxyalkylation of starchresults in uncontrolled degradation or decomposition of the starch. Whensuch products are used in the production of foams, the foams do not haveuniform chemical or physical properties.

A satisfactory process for utilizing starch as a compenent in thepreparation of polyurethane foams is disclosed in U.S. Pat. No.3,277,213. In this process, starch is added to a polyhydric alcoholcontaining at least two hydroxyl groups in a proportion equivalent to atleast 0.5 mole of the alcohol per mole of glucose unit weight of starchin the presence of an acid catalyst. The resulting mixture is thenoxyalkylated to yield a polyether polyol suitable for use in preparatingpolyurethane foams of excellent physical properties.

U.S. Pat. No. 3,674,717, discloses a process for preparingflame-retardant polyurethane foams by admixing starch with phosphoricacid at an elevated temperature and oxyethylating the resulting mixtureto yield a starch-phosphorus-based polyether useful as a reactant in thepreparation of urethane foams with flame-retardant properties.

Another method of producing flame retardant polyurethane foams, asdisclosed in U.S. Pat. No. 3,658,731 is by reacting either dry wheycontaining lactose or torula yeast protein with a polyisocyanate in thepresence of dimethyl sulfoxide. U.S. Pat. No. 3,629,162 discloses asimilar process. Both patents emphasize the important role of theprotein in the whey or yeast as a participant in the reaction.

British patent specification No. 1,440,831 claims the production ofisocyanurate foams by reactions of isocyanates with tri-, tetra- orhigher polysaccharides. The examples however, all require the presenceof conventional polyols. Moreover, the reactions require the presence ofisocyanurate ring producing catalysts as opposed to polyurethaneproducing catalysts.

An article in Journal of Cellular Plastics, August, 1967 by Bennett etal describes the preparation of polyurethane foams by reaction of aspecific polyol, N,N,N¹,N¹ -tetrakis(2-hydroxpropyl)ethylene diaminewith a polyisocyanate in non-aqueous media in the presence of starchcontaining not more than 10% moisture. Other products were similarlyprepared by replacing the starch with dextrin.

Yet another method for preparing flame-retardant polyurethane foams isdisclosed in Applicant's U.S. Pat. No. 4,291,129, wherein the foamcomposition is based on a polyurethane made from a polyisocyanate, aconventional industrial polyol, an aqueous slurry or solution ofuntreated carbohydrate, calcium acid phosphate, sodium aluminum sulfate,and sodium bicarbonate. The reactive mixture may contain one or moreflame retardants to produce flame resistant foams.

SUMMARY OF THE INVENTION

It has now been discovered that polyurethane foams which may containfire retardants can be prepared by reaction in an aqueous medium betweena polyisocyanate, a carbohydrate and water in the presence of asurfactant and a polyurethane producing catalyst. The reaction mixturemay contain sufficient flame retardant to impart flame resistance to thefoams produced. This is an improvement over Applicant's invention asdescribed in U.S. Pat. No. 4,291,129, in that the foam composition ismade without an industrial polyol. It is surprising to discover thatuseful foams can be produced from readily available, naturalcarbohydrates as complete replacements for conventional industrialpolyols.

The products of this invention are polyurethane foams produced byreaction between a polyisocyanate and an aqueous slurry or solution ofcarbohydrate such as cornstarch, corn syrup, fructose, dextrose,sucrose, molasses, cellulose and the like, in the presence of asurfactant and a polyurethane producing catalyst. Conventional additivessuch as flame retardants, surfactants, pigments, dyes, clays and otherorganic fillers, and the like may also be present.

Typical flame retardants which may be employed include, for example,sodium chloride, calcium chloride, borax, alkali-metal borates,tricresyl phosphate, tris(2-chloroethyl)phosphate,tris(chloropropyl)phosphate,O,O-diethyl-N,N-bis-(2-hydroethyl)aminomethyl phosphate, metal oxidesand chlorides such as antimony oxide, alumina, and antimony oxychloride.

The preferred carbohydrates are untreated carbohydrates, that is,carbohydrates which have not been treated to prevent oxidation or toblock any of the functional groups, e.g. oxyalkylation of hydroxylgroups. It refers to carbohydrates in which substantially all of thehydroxyl groups are free.

As in the usual foaming procedure, heat generated by the exothermicpolymerization reaction causes the water present in the reaction mixtureto vaporize. The vapors become entrapped in the foaming mixture as itrises to form the desired cellular structure. Varying the amount ofwater in the reaction system can be used as one type of controlprocedure to modify the density and cell structure of the foams toproduce products which may be employed for such divergent uses ashousehold sponges, hair curlers, cushions, packing materials, structuralmaterials, and flotation apparatus.

The foams of the present invention are especially useful to retrofitbuildings with insulation. For this use, they will usually be preparedin rigid form and will contain flame retardants. A particular advantageof such foams is that, unlike most polyurethane foams which melt andcollapse when they are exposed to flame, the foams of this inventiontend to maintain their cell structure even when exposed to hightemperatures. The foams of the present invention used for retrofitpurposes can be prepared under conditions which will generate very lowpressure during production so that they can conveniently be used asfoam-in-place insulation for existing structures without disengaging thewall parts.

The foams of the present invention can be produced in rigid, semi-rigidand flexible form. The rigid and semi-rigid foams can be converted toflexible foams which are particularly well suited for packaging andcushioning material. To effect this modification, the rigid orsemi-rigid foam as produced is fed through heavy rollers to reduce thefoam to approximately 2/3 of its original thickness. The conversion toflexible foam does not affect the fire retardant or other properties ofthe rigid foam.

Polyisocyanates which can be used in the present invention include, forexample, methylene diisocyanate; tolylene-2,4-diisocyanate;polymethylene polyphenyl isocyanate; tolylene-2,6-diisocyanate;diphenylmethane 4,4'-diisocyanate'3-methyldiphenylmethane-4,4'diisocyanate' m- andp-phenylenediisocyanate; naphthalene-1,5-diisocyanate; and mixtures ofthese products. Either crude or pure isocyanates can be used. Aprepolymer polymeric isocyanate which can be prepared by the reaction ofan excess of polyisocyanate with a lesser amount of a carbohydratepolyol having more than two hydroxyl groups per molecule can be used inthis invention. The combined use of more than two polyisocyanates isalso possible.

Water is used with the carbohydrate in the present invention to providea carrier for the carbohydrates and inorganic salts, and as explainedabove, is a blowing agent. The amount of water is some formulations iskept at the low end of the hereinafter described range to prevent"sighing", i.e., the collapse of the foam, as well as to aid in thereduction of the pressure of the foaming reaction.

As stated above, the water in the reaction mixture causes the evolutionof carbon dioxide, by the reaction of water with isocyanate. The carbondioxide functions as a blowing agent. For the purpose of adjusting thedensity of the rigid foams, auxiliary blowing agents such as low boilinghydrocarbons, carbon dioxide, or halohydrocarbons such aschlorofluoroalkanes can be utilized in the reaction mixture. This isanalogous to the conventional preparation of polyurethane foams, and thesame auxiliary blowing agents are employed. Suitable blowing agentswill, as is known, be chemically inert toward the reactants and haveboiling points below 100° C., preferably from -50° C. to 70° C. Suitablehalohydrocarbons include methylene chloride, ethylenetrichloride,trichloroomonofluoromethane, dichlorodifluoromethane,dichlorotetrafluoroethane, and dibromomonofluoroalkane.

For the preparation of the foams of this invention, the carbohydrate maybe added to the reaction mixture in the form of an aqueous slurry orsolution, which will hereinafter be referred to as a "syrup". Thecarbohydrate may be conrstarch, cellulose, corn syrup, dextrose,fructose, sucrose, molasses, or the like. The carbohydrate mixture whichpresently appears to be most suitable is corn syrup, a mixture ofsucrose and dextrose, and about 40% fructose. The high-fructose cornsyrup is less viscous than regular corn syrup and thus can be pouredmore readily. In addition, the syrup containing fructose gives a lowerdensity foam with more and smaller cells.

The preferred carbohydrates employed in this invention are watersoluble, mono- and disaccharides such as glucose, fructose and sucrose.These are the most readily available carbohydrates, the easiest to reactin aqueous media, and presently appear to give the most satisfactoryproducts, especially for packaging foams. The fact that reaction cantake place in a mixture containing a relatively high water contentmarkedly decreases the cost of the product.

Oligo and polysaccharides may be used to produce useful foams, butbecause of their lesser water solubility and reduced reactivity are lesspreferred. Unless the reaction conditions are appropriately selected,some unreacted carbohydrate may be dispersed in the finished foam. Inview of the disclosure of the Bennett et al article referred to above,it is surprising to find that useful products can be produced for thesepolymeric carbohydrates in the presence of large amounts of water.

The foams of this invention can be prepared by the usual prepolymer andone-shot procedures used with conventional polyols. The usualpolyurethane producing catalysts employed in these procedures are alsoapplicable with the process of this invention. These include tincompounds such as stannous octoate, stannous oleate, dibutyltindioctate, tributyltin acetate, dibutyltin diacetate and dibutyltindilaurate. The also include certain tertiary amine catalysts such asaliphatic tertiary amines, N-substituted morpholines andN,N'-substituted piperazines; more specifically, triethylamine,dimethylaminoethanol, diethylcyclohexylamine, lauryldimethylamine,triethanolamine, tetrakis(2-hydroxypropyl)ethylenediamine,N,N,N',N'-tetramethylethylenediamine, N-methylmorpholine,N-ethylmorpholine, bis(2-hydropropyl) 2-methylpiperazine,2,2,2-(diazabicyclooctane)triethylenediamine, 1,2,4-trimethylpiperazine,triethylenediamine, 2-methyl imidazole, 1,2-dimethyl imidazole, andother polyurethane producing catalysts known to those skilled in theart.

Other catalysts which have been found to be particularly useful in thepresent invention are aminohydroxy compounds, such as2-amino-2-methyl-1,1-propanol, tris-(hydroxymethyl)aminomethane, and2-amino-2-ethyl-1,3-propanediol.

Surfactants which have been found useful in the present inventioninclude, for example, Dow Corning (R) 92-5098 also known as DC 5098,which is a nonhydrolyzable silicone glycol copolymer. Union Carbide's(R) L 5420 is another nonhydrolyzable silicone glycol copolymer whichmay be used. Other surfactants include Air Products' LK-221 (R), LD-332,and LK-443, all organic surfactants which can be used as a totalreplacement for the usual silicone surfactants. Other Dow Corningsilicone surfactants which can be used in foams made according to thepresent invention include Dow Corning 190, 191, 193, 196, 197, 198,1312, F-11-630, 1315, Q2-5023 and Q2-5103.

In the presently preferred process for the production of foams inaccordance with this invention, two separate mixtures are first preparedand then blended together. The first mixture is a combination ofisocyanate and surfactant. If a flame retardant is employed, it isincorporated in this first mixture. The second mixture contains thecarbohydrate, the catalyst and water. Carbohydrate syrups arecommercially available containing varying amounts of water, up to about30% by weight. These syrups can be employed with or without the additionof supplemental water. Alternatively, a dry carbohydrate may be taken upin the selected amount of water.

The final foaming mixture of this invention will normally contain fromabout 5 to 30% polyisocyanate, 0.05 to 0.4% surfactant, 5 to 30% water,30 to 60% dry carbohydrate, 0.5 to 2.5% catalyst, all by weight based onthe total weight. As stated above, there may be components in the mixsuch as flame retardants, dyes, pigments and the like. The amount offlame retardants on a percent by weight basis is 5 to 11%.

The desired quantities of each component in the final mix can beobtained by mixing the first mixture with the second mixture at a firstto second ratio of from about 0.75:1 to 2:1 by weight, if the mixturescontain the following components in parts by weight based on the totalweight of each mixture.

    ______________________________________                                        First Mixture                                                                 5 to 200 parts by weight polyisocyanate                                       0.1 to 2.0 parts by weight surfactant                                         5 to 75 parts by weight flame retardant (optional)                            Second Mixture                                                                25 to 120 parts by weight carbohydrate                                        0.5 to 5 parts by weight catalyst                                             0.1 to 10 parts by weight auxiliary blowing                                   agent (optional)                                                              up to 30 parts by weight water                                                ______________________________________                                    

As aforesaid, a portion of the water may be provided as the carrier forthe carbohydrate, as in the case of commercial syrups.

There may be appreciable variation from the above defined quantitieswithout appreciable adverse effect on the reaction or on the productsproduced.

To make the foam according to the present invention, the mixture ofisocyanate and the mixture of carbohydrate syrup are thoroughly mixedtogether. The resulting mixture, which is liquid, may be introduced intoa mold or behind a wall to form the foam into the desired shape. Theingredients can be combined in a commercially available mixing gun forintroduction into a mold. The procedures employed are, in fact, the sameprocedures which are applicable to the preparation of foams withindustrial polyols.

The mixing ratio of isocyanate mix to carbohydrate mix is from 0.75:1 to2:1, preferably 1:1 to 1.5:1, by weight.

The flame retardant foams of this invention manifest excellentproperties when exposed to flame generating conditions. The followingresults have been achieved when samples of the foam have been testedunder tests recommended by Underwriter Laboratories and the AmericanSociety For Testing Materials.

    ______________________________________                                        ASTM E84-80   Flame Spread 20                                                 UL-94         94 VO Classification                                            ASTM 2863-77  Limiting oxygen index, more than                                              31%                                                             ASTM D-240-80 Heat of combustion - 8630 BTU/lb                                ______________________________________                                    

ASTM E-84-80--Steiner Tunnel Test is used to test and rate theperformance of building materials under high intensity fire conditions.The best fire rating given under this well known test procedure, ClassI, requires a flame spread of no higher than 25 on a scale which gives aflame spread value to untreated red oak of 100.

UL 94--Devised by Underwriters Laboratories, this procedure tests theflammability of plastic materials used for parts in devices andappliances in response to heat and flame under controlled laboratoryconditions. This vertical burn test provides for four classifications -94 V-0, 94 V-1, 94 V-2, and 94-5 V. The 94 V-0 classification is thebest given under this demanding flammability test procedure.

ASTM D-2863-77--This procedure measures how much oxygen is required (theLimiting Oxygen Index) to support flaming combustion and is used intesting various kinds of plastic materials.

Air under standard conditions contains just under 21% oxygen by volume.To support burning of the foam tested requires 48% more oxygen than iscontained in earth's atmosphere. A limiting oxygen index in excess of30% is quite high and indicates a material which will not burn exceptwith great difficulty under normal circumstances.

ASTM D-240-80--Emerson Bomb Calorimeter Test measures the amount of heat(Btu's per pound) that a given material contributes in a fire situationmeasured under specific laboratory conditions. It is assumed that thelower the figure obtained in this test, the less the material willcontribute in a real fire situation. The normal test figures forurethanes is 13,000 Btu's.

The following non-limiting examples are given by way of illustrationonly.

EXAMPLE 1

An isocyanate mix was containing 100 parts by weight polymethylenepolyphenyl isocyanate (Mobay MONDUR MR), 1 part by weight Union CarbideL 5340 surfactant, and 25 parts by weight Stauffer FYROL CEFtris(2-chloroethyl)phosphate, flame retardant. A carbohydrate syrup mixwas made containing 100 parts by weight corn syrup (about 6% water) andone part by weight 2-amino-2-methyl-1-propanol catalyst. The twomixtures were mixed in a mixing tank of suitable capacity with anelectric mixer. The final mixture was poured into a mold simulating awall cavity, where it foamed and provided excellent bonding to all thesurfaces of the mold.

EXAMPLE 2

An isocyanate mix was made containing 100 parts by weight polymethylenepolyphenyl isocyanate (Mobay MONDUR MR), 1 part by weight Dow Q2 5098silicone surfactant, and 20 parts by weight Stauffer FYROL CEF,tris(2-chloroethyl)phosphate, flame retardant. A carbohydrate syrup mixwas made containing 100 parts by weight high-fructose corn syrup (about40% fructose, 6% water) and one part by weight2-amino-2-methyl-1-propanol catalyst. The two mixtures were mixed in amixing tank of suitable capacity with an electric mixer. The finalmixture was poured into a mold, where it foamed and provided excellentbonding to all surfaces of the mold. The foam was lighter in weight andhad more and smaller cells than the foam of Example 1.

EXAMPLE 3

A rigid polyurethane foam made according to the process of Example 1 wasprepared in the form of a slab 3 inches thick. The slab was crushedbetween rollers to a thickness of about 2 inches. The resulting flexiblefoam retained its flame retardancy, making it suitable for use as apackaging material.

EXAMPLES 4 TO 20

A variety of foams of differing densities were prepared from foamingreactants containing different catalysts and different surfactants.

The procedure was to mix the carbohydrate syrup (Isosweet 5500, a highfructose corn syrup available from Staley Industrial Products containingprincipally fructose and dextrose at a solids content of about 75% andwater content of about 25%) and the catalyst in a small plasticcontainer. The polyisocyanate, flame retardant and surfactant were mixedin another plastic container. The two compositions were thoroughly mixedand poured into a mold. The foam was allowed to freely rise in the moldand then left standing for a few hours to cure. The results are shownbelow. The surfactants are silicone surfactants available from UnionCarbide (UC) and Dow Corning (DC). The catalysts identified by thedesignation D-T is Dabco T available from Air Products, Inc. TheA-designation refers to catalysts available from Union Carbide. Thecatalysts are all understood to be tertiary amines.

    ______________________________________                                        EXAMPLE  SURFACTANT    CATALYST   DENSITY                                     ______________________________________                                        4        UC 5340       D-T        0.917                                       5        UC 5350       A-10       0.906                                       6        UC 540        D-T        0.927                                       7        UC 540        A-10       0.965                                       8        UC 540        D-T        0.967                                       9        UC 540        A-1        0.921                                       10       UC 5420       D-T        0.954                                       11       UC 5420       A-10       1.013                                       12       UC 5421       D-T        0.956                                       13       UC 5421       A-1        0.860                                       14       UC 5750       A-1        0.959                                       15       UC 5750       A-10       1.072                                       16       DC 193        D-T        0.970                                       17       DC 193        A-1        1.008                                       18       DC 5098       D-T        0.930                                       19       LK 221        D-T        1.008                                       20       LK 443        D-T        0.966                                       ______________________________________                                    

The reactants in parts by weight were as follows:

    ______________________________________                                        Isosweet 5500 98                                                              Catalyst      2                                                               MONDUR MR     105                                                             CEF           45                                                              Surfactant    Variable from 0.1 to 1                                          ______________________________________                                    

EXAMPLES 21 TO 26

A similar set of examples was conducted utilizing the same catalysts andsurfactants, but varying the polyisocyanate. The results are shownbelow.

    ______________________________________                                                              SURFAC-   CATA-  DEN-                                   EXAMPLE  ISOCYANATE   TANT      LYST   SITY                                   ______________________________________                                        21       Mondur MR    UC 5340   D-T    1.125                                  22       Luprinate M-20                                                                             UC 5340   D-T    1.062                                  23       Papi 20      UC 5340   D-T    1.092                                  24       Papi 29      UC 5340   D-T    0.907                                  25       Papi 135     UC 5340   D-T    0.889                                  26       Papi 580     UC 5340   D-T    1.130                                  ______________________________________                                    

Mondur MR is available from Mobay, Luprinate is available fromBASF-Wyandotte and Papi is available from Upjohn. All are understood tobe principally 4,4'-diphenylmethane diisocyanate.

EXAMPLE 27

In a one quart wax lined paper cup, 10 parts by weight of water weremixed with 90 parts by weight sucrose by rapid stirring at 2200 rpm witha stirrer with a 2 inch diameter double 3 blade marine type propellerfor 30 seconds. To this slurry there was added 150 parts by weight ofMobay E-534 isocyanate blend, and stirring was continued for 15 seconds.The mix was poured into an 8" by 8" by 6" mold at ambient temperature.The resulting foam was well formed, of good appearance and would beclassified as a rigid or semi-rigid foam.

Mobay E-534 is a blend of 70 parts by weight Mondur MR, 30 parts byweight CEF and 1 part by weight Dow Corning 5098 silicone surfactant.

EXAMPLE 28

The procedure of Example 27 was repeated replacing the sucrose withdextrose. The results were substantially the same.

EXAMPLE 29

Example 27 was repeated except that before the E-534 was added to thesucrose slurry, sufficient Freon-F-11 was added to a constant weightinto the sucrose slurry so that it contained 10 parts by weight of theauxiliary blowing agent.

The resulting foam was of somewhat lower density than the foam ofExample 27, but, both foams were similar in appearance.

EXAMPLE 30

Example 28 was repeated except that before the E-534 was added to thedextrose slurry, sufficient methylene dichloride was added to a constantweight into the dextrose slurry so that it contained 5 parts by weightof the auxiliary blowing agent.

The resulting foam was of somewhat lower density than the foam ofExample 28, but both foams were similar. in appearance.

What is claimed is:
 1. A mixture useful for the preparation ofpolyurethane foams comprising an untreated carbohydrate in whichsubstantially all of the hydroxyl groups are free, water and apolyurethane producing catalyst.
 2. A mixture as in claim 1 comprisingfrom 25 to 120 parts by weight carbohydrate, 0.5 to 5 parts by weightcatalyst and up to 30 parts by weight water, all based on the totalweight.
 3. A mixture as in claim 1 or 2 wherein the carbohydrate isselected from the group consisting of cornstarch, cellulose, corn syrup,dextrose, sucrose and molasses.
 4. A mixture as in claim 1 or 2 whereinthe carbohydrate is cornstarch.
 5. A mixture as in claim 1 or 2 whereinthe carbohydrate is corn syrup.
 6. A mixture as in claim 1 or 2 whereinthe catalyst is selected from the group consisting of stannous octoate,stannous oleate, dibutyltin dioctate, tributyltin acetate, dibutyltindiacetate, dibutyltin dilaurate, triethylamine, dimethylaminoethanol,diethylcyclohexylamine, lauryldimethylamine, triethanolamine,tetrakis(2-hydroxypropyl)ethylenediamine,N,N,N',N'-tetramethylethylenediamine, N-methylpiperazine,2,2,2-(diazabicyclooctane)triethylenediamine, 1,2,4-trimethylpiperazine,triethylenediamine, 2-methyl imidazole, 1,2-dimethyl imidazole,2-amino-2-methyl-1,1-propanol, tris-(hydroxymethyl)aminomethane,2-amino-2-ethyl-1,3-propanediol.
 7. A mixture as in claim 1 or 2 whereinthe carbohydrate is selected from the group consisting of cornstarch,cellulose, corn syrup, dextrose, sucrose and molasses, and the catalystis selected from the group consisting of stannous octoate, stannousoleate, dibutyltin dioctate, tributyltin acetate, dibutyltin diacetate,dibutyltin dilaurate, triethylamine, dimethylaminoethanol,diethylcyclohexylamine, lauryldimethylamine, triethanolamine,tetrakis(2-hydroxypropyl)ethylenediamine,N,N,N',N'-tetramethylethylenediamine, N-methylpiperazine,2,2,2-(diazabicyclooctane)triethylenediamine, 1,2,4-trimethylpiperazine,triethylenediamine, 2-methyl imidazole, 1,2-dimethyl imidazole,2-amino-2-methyl-1,1-propanol, tris-(hydroxymethyl) aminomethane,2-amino-2-ethyl-1,3-propanediol.
 8. A mixture as in claim 1 or 2 whereinthe carbohydrate is corn syrup and the catalyst is selected from thegroup consisting of stannous octoate, stannous oleate, dibutyltindioctate, tributyltin acetate, dibutyltin ethanol,diethylcyclohexylamine, lauryldimethylamine, triethanolamine,tetrakis(2-hydroxypropyl)ethylenediamine,N,N,N',N'-tetramethylethylenediamine, N-methylpiperazine,2,2,2-(diazabicyclooctane)triethylenediamine, 1,2,4-trimethylpiperazine,triethylenediamine, 2-methyl imidazole, 1,2-dimethyl imidazole,2-amino-2-methyl-1,1-propanol, tris-(hydroxymethyl)aminomethane,2-amino-2-ethyl-1,3-propanediol.
 9. A mixture as in claim 1 or 2 whereinthe carbohydrate is corn syrup and the catalyst is selected from thegroup consisting of stannous octoate, stannous oleate, dibutyltindioctate, tributyltin acetate, dibutyltin diacetate, dibutyltindilaurate, triethylamine, dimethylaminoethanol, diethylcyclohexylamine,lauryldimethylamine, triethanolamine,tetrakis(2-hydroxypropyl)ethylenediamine,N,N,N',N'-tetramethylethylenediamine, 1,2,4-trimethylpiperazine,triethylenediamine, 2-methyl imidazole, 1,2-dimethyl imidazole,2-amino-2-methyl-1,1-propanol, tris-(hydroxymethyl)aminomethane,2-amino-2-ethyl-1,3-propanediol.